The factors contributing to the development of post-operative dentofacial and occlusal deformities in the cleft palate patients are incompletely understood. Longitudinal dentofacial growth data of the H.K. Cooper Clinic have demonstrated a pattern of development characteristic of patients with chronic naso-respiratory obstruction. Fifty patients from this longitudinal growth study were chosen to test the hypothesis that airway obstruction in the cleft palate patient is a major contributor in the creation of the observed long-term dentofacial growth changes. All subjects had partial obliteration of the velopharyngeal port by pharyngeal flap surgery for treatment of hypernasal speech. This sample consists of l6 bilateral clefts, 8 unilateral clefts, and 26 isolated cleft palates. The average age at time of pharyngeal flap surgery was 7 years, 4 mos. and all patients were followed longitudinally with yearly serial lateral and frontal cephalometric radiographs and dental casts. The proposed study will select skeletal and dental measures of height and depth, to identify patterns and rates of facial growth post-surgically which deviate from the presurgical state. Comparison of this exerimental group with a sample of cleft patients matched for age, sex and cleft type but without pharyngeal flaps will be used to identify post-pharyngeal flap growth deviations from those expected in the absence of partial airway obstruction produced by the flaps. Finally, additional data collection will be undertaken, prospectively, on new patients planned for pharyngeal flap surgery, to increase the data base, and expand analysis to include more physiological measures of airway resistance such as pressure/flow and cineradiographic techniques.